Is Blender Cycles rendering, killing my CPU?
Cycles, by nature, is very realistic at the cost of computer power. I frequently have to click my fans into full gear when rendering Cycles, just to not go over 80˚C.
If using a cooler is simply out of the question than I suggest you reduce the number of threads Cycles uses. This may reduce the strain enough that your temperature stays within a reasonable range.
The thread count can be found under properties&gt;render&gt;performance&gt;threads:

Other than that you could try baking, rendering at a lower resolution, and simplifying your geometry. As for the temperature itself, 100˚ Fahrenheit isn't hot, but I made the assumption that you are talking Celsius.
As a last note, I believe it's worth mentioning that entering render mode in the 3d viewport, is nearly as hard on your computer as just rendering images, with the main performance difference being modifiers hidden from view, and lower view samples.